Stroke is the third leading cause of death and leading cause of disability in adults in the US. Nearly 800,000 people suffer a stroke annually, and more than 143,000 deaths occur as a result. Hispanic Americans are the fastest growing minority population in the US, as well as the most numerous. The majority of Hispanic Americans are of Mexican descent. Mexican Americans (MAs) have an increased risk of stroke especially at younger ages when disability has the greatest impact. Reasons for increased stroke risk in MAs are not fully understood but traditional risk factors are not likely to fully account for the increased stroke burden in this population. Chronic infectious pathogens have been proposed as risk factors for stroke and for poor stroke outcome, although the evidence remains inconclusive and studies have not been done in MAs. As chronic infections are more prevalent in MAs than their non-Hispanic white counterparts, this risk factor may be particularly important for this population. The proposed dissertation research seeks to examine the links between chronic infection and incident stroke and post-stroke functional outcome, among participants from the Sacramento Area Latino Study on Aging (SALSA). This research will extend current knowledge of infection and stroke in several critical ways:1) by examining antibody response to several infectious agents versus infection serostatus as independent risk factors for stroke, 2) by examining the underlying mechanisms, including inflammatory pathways, by which antibody response may influence stroke risk, 3) by investigating the association of antibody response to post-stroke functional outcomes and 4) by focusing specifically in a MA population known to experience a greater stroke burden as well as a greater infection burden. The recognition that infection increases stroke risk after accounting for traditional risk factors may have important implications for the prevention of stroke in MAs and for reducing the stroke health disparity in this population. In addition to advancing the science in this critical area, the proposed fellowship will provide the rigorous training, including coursework and seminars/workshops, interaction with stroke neurologists and epidemiologists and hands-on training in population-based studies and laboratory methods, needed to develop the applicant from a doctoral student to an independent investigator who will devote her research career to the study of stroke and its determinants, including infection.